Finally managed to get through. My main problem was I kept getting spotted trying to shoot the far left car first so I shot the one behind me, then the far left, went to barrier, shot the center one,...

In the beginning of Chapter 5, I'm kind of stuck. I go through pushing the boxes and the car, as well as having Amy go through the pipe. Can get through the glass but after that, can't seem to figure...

Gunner and Quartermaster are part of the Queen Anne's Revenge crew (Blackbeard's ship). Syrena swims underwater but if hold B to do her singing, she walks. Admittedly not sure if she's needed - I did...

Confirming this list: You need Quartermaster, Gunner and Syrena. Also note, not sure if it was mentioned, but it needs to be done in one go. I tried just doing the three I missed after I had shut off...